Postfix+MySQL Problem

I've got a problem with the Postfix+MySQL setup (running Ubuntu Breezy). It will deliver mail just fine for a while (maybe an hour or so), and then it will just stop delivering mail. Here's a sampling of the log file for what seems to be a single piece of incoming mail:

That first part seems to be the root of the problem. MySQL is blocking connections to this database from localhost because of too many interrupted connection requests (according to the MySQL docs). The easiest solution would be to whitelist localhost somehow so that MySQL will never block it (no matter how many interrupted requests it gets from it), however, I can't find any documentation to suggest that this is even possible. I'd really like to know what is causing the problem.